1. Technical Field
The present disclosure relates to an overdrive technology for use in an electro-optical device.
2. Related Art
As a technology for increasing the response speed of liquid crystal in a liquid crystal display device, there is a technology called “overdrive technology.” JPA-2009-128504, for example, describes a liquid crystal display device using this technology. In the liquid crystal display device, one frame is divided into a plurality of fields, and the liquid crystal is AC driven. Then, when a frame changes, overdrive processing is performed in the first field of a subsequent frame but is not performed in the other field(s) of the subsequent frame. This liquid crystal display device is also configured so that the polarity of a voltage to be applied to the liquid crystal is changed in the first field in each frame. Thus, the polarity of the voltage to be applied to the liquid crystal when overdrive is performed changes alternately between the positive polarity and the negative polarity in each frame.
In the liquid crystal display device described in JP-A-2009-128504, the polarity of the voltage to be applied to the liquid crystal when overdrive processing is performed is not fixed to one of the positive polarity and the negative polarity but alternately changes between the positive polarity and the negative polarity. Thus, as compared to a configuration in which the polarity of the voltage to be applied to the liquid crystal when overdrive processing is performed is fixed to one of the positive polarity and the negative polarity, it is considered that the probability of a DC voltage component being applied to the liquid crystal can be reduced.
However, in the case of a moving image, there might be cases where the gray-scale level does not change before and after a frame changes. If the gray-scale level does not change, overdrive processing is not performed. In this case, for example, after a voltage having the positive polarity is applied, a voltage having the negative polarity is not applied, and a DC component is applied to the liquid crystal. Also, in the liquid crystal display device of JPA-2009-128504, for a pixel, when the gray-scale level changes, the correction amount adopted when a voltage of the positive polarity is applied is not equal to the correction amount adopted when a voltage having the negative polarity is applied, and the correction amounts for overdrive might differ. For example, the correction amount adopted when a voltage having the positive polarity is applied is continuously larger than the correction amount adopted when a voltage having the negative polarity is applied, a DC voltage component is applied to the liquid crystal.